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Data Cube Measures: Three Categories

• Distributive: if the result derived by applying the function to n aggregate values is the same as that derived by applying the function on all the data without partitioning
• E.g., count(), sum(), min(), max()
• Algebraic: if it can be computed by an algebraic function with M arguments (where M is a bounded integer), each of which is obtained by applying a distributive aggregate function
• E.g., avg(), min_N(), standard_deviation()
• Holistic: if there is no constant bound on the storage size needed to describe a subaggregate.
• E.g., median(), mode(), rank()